Janus Gel Polymer Electrolyte: Asymmetric Structure Design for Anti‐CO 2 in Flexible Zinc‐Air Batteries

ABSTRACT Alkaline gel electrolytes in flexible zinc‐air batteries (FZABs) suffer from CO 2 poisoning and water loss, causing decreased conductivity and carbonate crystal blockage. This work presents a Janus asymmetric PVA/PSSA‑K 2 CO 3 gel polymer electrolyte (GPE) fabricated via a non‐solvent induced phase separation (NIPS) method, which simultaneously provides. PVA, PSSA, and K 2 CO 3 are polyvinyl alcohol, poly(4‐styrenesulfonic acid), and potassium carbonate, respectively. The top dense layer (pores ∼0.28 µm) physically inhibits CO 2 diffusion and ensures H 2 O retention, ensuring conductivity. The bulk spongy layer (pores ∼1.25 µm) stores OH − and CO 3 2− for rapid transport. Pre‑embedded CO 3 2− acts as a chemical barrier, shifting the reaction CO 2 + 2OH − ⇌ CO 3 2− + H 2 O leftward to suppress carbonate crystallization. A FZAB using this GPE and Pt/C+RuO 2 cathode achieves 93.5 mS cm −1 ionic conductivity, 121.3 mW cm −2 peak power density, and prolonged cycling life in a 10 v% CO 2 atmosphere. Replacing Pt/C+RuO 2 with tri‑site FeCo SA/NP @NGA‑600 further enhances performance due to faster cathode kinetics. This study demonstrates an effective design strategy combining Janus GPE and tri‐site catalysts for high‑performance alkaline flexible ZABs.